我有一个使用视图寻呼机在片段之间切换的活动。我有三个片段。在这些片段之间切换时，我必须将一个字符串值传递给片段类，以识别选择哪个片段。因为这里我对所有三个片段使用相同的片段类。 这是我的主要活动。
public class mainActivity extends AppCompatActivity {
public String kind, value;
private TabLayout tabLayout;
private ViewPager viewPager;
public FloatingActionButton upload, send;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main_activity);
upload = (FloatingActionButton) findViewById(R.id.upload_fab);
send = (FloatingActionButton) findViewById(R.id.send_message);
uploadFab.hide();
Intent mIntent = getIntent();
kind = mIntent.getStringExtra("KIND");
viewPager = (ViewPager) findViewById(R.id.viewpager);
setupViewPager(viewPager);
tabLayout = (TabLayout) findViewById(R.id.tabs);
tabLayout.setupWithViewPager(viewPager);
viewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
}
@Override
public void onPageSelected(int position) {
Student student =new Student();
switch (position) {
case 0:
upload.hide();
value = "r";
break;
case 1:
upload.hide();
value = "e";
break;
case 2:
upload.show();
value = "u";
break;
default:
upload.hide();
val = "r";
break;
}
}
@Override
public void onPageScrollStateChanged(int state) {
}
});
}
private void setupViewPager(ViewPager viewPager) {
ViewPagerAdapter adapter = new ViewPagerAdapter(getSupportFragmentManager());
adapter.addFragment(new RemainderFragment(), "REMAINDER");
adapter.addFragment(new RemainderFragment(), "EMAIL");
adapter.addFragment(new RemainderFragment(), "UPLOAD");
viewPager.setAdapter(adapter);
}
class ViewPagerAdapter extends FragmentPagerAdapter {
private final List<Fragment> mFragmentList = new ArrayList<>();
private final List<String> mFragmentTitleList = new ArrayList<>();
public ViewPagerAdapter(FragmentManager manager) {
super(manager);
}
@Override
public Fragment getItem(int position) {
return mFragmentList.get(position);
}
@Override
public int getCount() {
return mFragmentList.size();
}
public void addFragment(Fragment fragment, String title) {
mFragmentList.add(fragment);
mFragmentTitleList.add(title);
}
@Override
public CharSequence getPageTitle(int position) {
return mFragmentTitleList.get(position);
}
}
这是我的片段类
public class RemainderFragment extends Fragment {
public RemainderEmailFragment() {
// Required empty public constructor
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
ViewGroup rootView = (ViewGroup) inflater.inflate(R.layout.raminder_fragment, container, false);
EditText subject = (EditText) rootView.findViewById(R.id.subject);
EditText des = (EditText) rootView.findViewById(R.id.description);
// String value = mainActivity.value
//button to send data
button = activity.send;
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
//getting details
SendData();
}
});
return rootView;
}
public void SendData() {
//functon
}
我尝试过Intent和共享首选项来发送数据。但没有任何效果。我必须在我的片段类中获取String值。请帮忙。
答案 0 :(得分：0)
请检查以下代码以获取所需的示例更改，我已修改您的文件并添加了一些代码以支持您的要求。
package com.adobe.reader.test;
import java.util.ArrayList;
import java.util.List;
import android.content.Intent;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.TabLayout;
import android.support.v4.app.Fragment;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import com.adobe.reader.R;
public class mainActivity extends AppCompatActivity
{
public String kind, value;
private TabLayout tabLayout;
private ViewPager viewPager;
public FloatingActionButton upload, send;
// Adding adapter
private ViewPagerAdapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main_activity);
upload = (FloatingActionButton) findViewById(R.id.upload_fab);
send = (FloatingActionButton) findViewById(R.id.send_message);
uploadFab.hide();
Intent mIntent = getIntent();
kind = mIntent.getStringExtra("KIND");
viewPager = (ViewPager) findViewById(R.id.viewpager);
setupViewPager(viewPager);
tabLayout = (TabLayout) findViewById(R.id.tabs);
tabLayout.setupWithViewPager(viewPager);
// Let's say we need to call some method from fragment in the activity
Fragment fragment = getCurrentFragment();
if (Fragment instanceof RemainderFragment)
{
RemainderFragment remainderFragment = (RemainderFragment) fragment;
remainderFragment.setString("Testing string");
}
viewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
}
@Override
public void onPageSelected(int position) {
Fragment fragment = getCurrentFragment();
if (Fragment instanceof RemainderFragment)
{
RemainderFragment remainderFragment = (RemainderFragment) fragment;
}
Student student =new Student();
switch (position) {
case 0:
upload.hide();
value = "r";
break;
case 1:
upload.hide();
value = "e";
break;
case 2:
upload.show();
value = "u";
break;
default:
upload.hide();
val = "r";
break;
}
remainderFragment.setString(value);
}
@Override
public void onPageScrollStateChanged(int state) {
}
});
}
/**
* This method will give you current fragment used in the viewpager.
* @return
*/
public Fragment getCurrentFragment()
{
Fragment fragment = null;
if (viewPager != null)
{
int currentFragmentIndex = viewPager.getCurrentItem();
if (adapter != null)
{
fragment = adapter.getItem(currentFragmentIndex);
}
}
return fragment;
}
private void setupViewPager(ViewPager viewPager) {
ViewPagerAdapter adapter = new ViewPagerAdapter(getSupportFragmentManager());
adapter.addFragment(new RemainderFragment(), "REMAINDER");
adapter.addFragment(new RemainderFragment(), "EMAIL");
adapter.addFragment(new RemainderFragment(), "UPLOAD");
viewPager.setAdapter(adapter);
}
class ViewPagerAdapter extends FragmentPagerAdapter {
private final List<Fragment> mFragmentList = new ArrayList<>();
private final List<String> mFragmentTitleList = new ArrayList<>();
public ViewPagerAdapter(FragmentManager manager) {
super(manager);
}
@Override
public Fragment getItem(int position) {
return mFragmentList.get(position);
}
@Override
public int getCount() {
return mFragmentList.size();
}
public void addFragment(Fragment fragment, String title) {
mFragmentList.add(fragment);
mFragmentTitleList.add(title);
}
@Override
public CharSequence getPageTitle(int position) {
return mFragmentTitleList.get(position);
}
}
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.EditText;
import com.adobe.reader.R;
public class RemainderFragment extends Fragment
{
public String testingString;
public RemainderEmailFragment() {
// Required empty public constructor
}
// Sample method to be called from activity
public void setString(String testStr)
{
testingString = testStr;
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
ViewGroup rootView = (ViewGroup) inflater.inflate(R.layout.raminder_fragment, container, false);
EditText subject = (EditText) rootView.findViewById(R.id.subject);
EditText des = (EditText) rootView.findViewById(R.id.description);
// String value = mainActivity.value
//button to send data
button = activity.send;
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
//getting details
SendData();
}
});
return rootView;
}
public void SendData() {
//functon
}